Issue #23074: asyncio.get_event_loop() now raises an exception if the thread

has no event loop even if assertions are disabled.

Lib/asyncio/base_events.py

@@ -420,7 +420,7 @@ class BaseEventLoop(events.AbstractEventLoop):
         """
         try:
             current = events.get_event_loop()
-        except AssertionError:
+        except RuntimeError:
             return
         if current is not self:
             raise RuntimeError(

Lib/asyncio/events.py

@@ -517,9 +517,9 @@ class BaseDefaultEventLoopPolicy(AbstractEventLoopPolicy):
             not self._local._set_called and
             isinstance(threading.current_thread(), threading._MainThread)):
             self.set_event_loop(self.new_event_loop())
-        assert self._local._loop is not None, \
+        if self._local._loop is None:
-               ('There is no current event loop in thread %r.' %
+            raise RuntimeError('There is no current event loop in thread %r.'
-                threading.current_thread().name)
+                               % threading.current_thread().name)
         return self._local._loop
 
     def set_event_loop(self, loop):

Lib/test/test_asyncio/test_events.py

@@ -2252,14 +2252,14 @@ class PolicyTests(unittest.TestCase):
     def test_get_event_loop_after_set_none(self):
         policy = asyncio.DefaultEventLoopPolicy()
         policy.set_event_loop(None)
-        self.assertRaises(AssertionError, policy.get_event_loop)
+        self.assertRaises(RuntimeError, policy.get_event_loop)
 
     @mock.patch('asyncio.events.threading.current_thread')
     def test_get_event_loop_thread(self, m_current_thread):
 
         def f():
             policy = asyncio.DefaultEventLoopPolicy()
-            self.assertRaises(AssertionError, policy.get_event_loop)
+            self.assertRaises(RuntimeError, policy.get_event_loop)
 
         th = threading.Thread(target=f)
         th.start()